26. Paul McCartney's ex-wife only had one leg--didn't stop her.

An illness or some other condition that must be overcome (like weight or a missing leg) makes the challenge more interesting to the viewer. It's part dance contest and part popularity contest--perhaps she didn't feel sufficiently popular?

She probably has two left feet, or she doesn't want to deal with the riff-raff on a regular basis. I thank her for her decision; my family watches that program!